syzbot

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WARNING: possible recursive locking detected
5.15.153-syzkaller #0 Not tainted
--------------------------------------------
syz-executor178/3499 is trying to acquire lock:
ffff8880790b80b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x16a/0x1e0

but task is already holding lock:
ffff8880790b80b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x16a/0x1e0

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&tree->tree_lock/1);
  lock(&tree->tree_lock/1);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

5 locks held by syz-executor178/3499:
 #0: ffff8880790be460 (sb_writers#9){.+.+}-{0:0}, at: vfs_write+0x29a/0xe50 fs/read_write.c:590
 #1: ffff888016591628 (&sb->s_type->i_mutex_key#15){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline]
 #1: ffff888016591628 (&sb->s_type->i_mutex_key#15){+.+.}-{3:3}, at: generic_file_write_iter+0x7c/0x1b0 mm/filemap.c:3941
 #2: ffff888016591478 (&HFS_I(inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xfb/0x1440 fs/hfs/extent.c:397
 #3: ffff8880790b80b0 (&tree->tree_lock/1){+.+.}-{3:3}, at: hfs_find_init+0x16a/0x1e0
 #4: ffff8880165900f8 (&HFS_I(tree->inode)->extents_lock){+.+.}-{3:3}, at: hfs_extend_file+0xfb/0x1440 fs/hfs/extent.c:397

stack backtrace:
CPU: 1 PID: 3499 Comm: syz-executor178 Not tainted 5.15.153-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2946 [inline]
 check_deadlock kernel/locking/lockdep.c:2989 [inline]
 validate_chain+0x46d2/0x5930 kernel/locking/lockdep.c:3775
 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012
 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
 __mutex_lock_common+0x1da/0x25a0 kernel/locking/mutex.c:596
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 hfs_find_init+0x16a/0x1e0
 hfs_ext_read_extent fs/hfs/extent.c:200 [inline]
 hfs_extend_file+0x317/0x1440 fs/hfs/extent.c:401
 hfs_bmap_reserve+0xd5/0x3f0 fs/hfs/btree.c:231
 __hfs_ext_write_extent+0x22e/0x4f0 fs/hfs/extent.c:121
 __hfs_ext_cache_extent+0x6a/0x990 fs/hfs/extent.c:174
 hfs_ext_read_extent fs/hfs/extent.c:202 [inline]
 hfs_extend_file+0x340/0x1440 fs/hfs/extent.c:401
 hfs_get_block+0x3e0/0xb60 fs/hfs/extent.c:353
 __block_write_begin_int+0x60b/0x1650 fs/buffer.c:2012
 __block_write_begin fs/buffer.c:2062 [inline]
 block_write_begin fs/buffer.c:2122 [inline]
 cont_write_begin+0x5d6/0x840 fs/buffer.c:2471
 hfs_write_begin+0x92/0xd0 fs/hfs/inode.c:59
 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785
 __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912
 generic_file_write_iter+0xa7/0x1b0 mm/filemap.c:3944
 call_write_iter include/linux/fs.h:2148 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0xacf/0xe50 fs/read_write.c:594
 ksys_write+0x1a2/0x2c0 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fbb13e2ff19
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd2f8fd188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fbb13e79095 RCX: 00007fbb13e2ff19
RDX: 000000000208e24b RSI: 0000000020000080 RDI: 0000000000000005
RBP: 00007fbb13e7909d R08: 0000555556c564c0 R09: 0000555556c564c0
R10: 0000555556c564c0 R11: 0000000000000246 R12: 00007ffd2f8fd1b0
R13: 00007ffd2f8fd3d8 R14: 431bde82d7b634db R15: 00007fbb13e7903b
 </TASK>